Heating and cooling systems in most homes are controlled by a thermostat which is set to a threshold temperature. In heating mode, when the room temperature drops below the threshold temperature, the heating system is activated to heat the home. In cooling mode, when the room temperature rises above the threshold temperature, the cooling system is activated to cool the home.
To save energy, it is desirable to adjust the thermostat's threshold temperature to an offset temperature when the occupants of the home are away. For example, significant energy savings may result by using an offset temperature of 10 degrees below the normal threshold temperature for the heating mode, or 10 degrees above the normal threshold temperature for the cooling mode.
In order to realize the potential energy savings of an offsetable thermostat, offset temperatures must be easy to initially program into the thermostat, and easy to activate once programmed. If the programming and use of an offsetable thermostat is not easy and intuitive, users are likely to become frustrated with it and not use it, thus forgoing possible energy and money savings.
Also, there are often times when a user intends to activate a temperature offset before leaving home, but forgets to do so until the user is a long distance from home. Sometimes, the user remembers to activate the temperature offset while leaving the home, such as when getting in the car to drive away. In such situations, it is desirable to be able to remotely activate the offset temperature, such as from the car while backing out of the driveway of the home, or from a hotel room that is hundreds of miles away from the home.
Therefore, a thermostat is needed that provides offset temperatures for energy savings, that is easy to program and operate, and that may be operated remotely, either from a few feet away or a few hundred miles away.